In great consideration of sealing properties, elastic bodies (e.g. rubber) are used for parts that slide while maintaining their, sealing performance, such as gaskets each of which is integrated with a syringe plunger and forms a seal between the plunger and the barrel. Such elastic bodies, however, have a slight problem with their sliding properties (see Patent Literature 1). Hence, a sliding property improving agent (e.g. silicone oil) is applied to the sliding surface. It is pointed out, however, that silicone oil can have a baleful influence on recently marketed bio-preparations. On the other hand, a gasket to which a sliding property improving agent is not applied is poor in the sliding properties, and thus the plunger cannot be pushed smoothly so that it pulsates upon administration, thereby causing problems such as inaccurate injection amount and pain on patients.
In order to simultaneously satisfy such conflicting requirements, that is, the sealing properties and the sliding properties, one technique is proposed in which a self-lubricating PTFE film is applied (see Patent Literature 2). The film, however, is generally expensive and thus increases the production cost of processed products, limiting its application range. Also, products covered with the PTFE film might not be reliable in the case that the products are used in applications in which sliding or the like motion is repeated and durability is thereby required. Another problem is that since PTFE is vulnerable to radiation, it cannot be sterilized by radiation.
Meanwhile, application to other uses requiring sliding properties in the presence of water may be considered. Specifically, water can be delivered without a loss by reducing the fluid resistance of the inner surface of a pre-filled syringe or the inner surface of a pipe or tube for delivering water, or by making its contact angle with water high or greatly low. Also, drainage of water on wet roads and of snow on snowy roads can be improved by reducing the fluid resistance of the groove surface of tires, or by making its contact angle with water high or greatly low. This results in enhanced grip performance and enhanced hydroplaning properties, leading to better safety. In addition, less sticking of wastes and dusts is expected as a result of reducing the sliding resistance of the sidewall surface of tires or walls of buildings, or as a result of making its or their contact angle with water high.
Further advantageous effects can be expected, such as: less pressure loss when water, an aqueous solution, or the like is delivered through a diaphragm such as a diaphragm pump or a diaphragm valve; easy sliding of skis or a snowboard by enhancing the sliding properties of the sliding surface thereof; better noticeability of a road sign or a signboard by enhancing the sliding properties thereof to allow snow to slide easily; reduction in water resistance or drag and less sticking of bacteria on the outer peripheries of a ship by reducing the sliding resistance of the outer peripheries or by making their contact angle with water high; and swimsuits with reduced water resistance or drag by improving the sliding properties of the thread surface thereof.